Method of and apparatus for manufacturing bielastic tapes



June 15, 1954 B, LIEBQWITZ 2,681,019

METHOD OF AND APPARATUS FOR MANUFACTURING BIELASTIC TAPES Filed March18, 1952 I 2 Sheets-Sheet 1 INVENTOR.

9E :rAn m L|E8ourrz June 15, 1954 a. LIEBOWITZ 2,681,0

METHOD OF AND APPARATUS FOR MANUFACTURING BIELASTIC TAPES Filed March18, 1952 2 Sheets-Sheet 2 PAS 74A CE INVENTOR. BEHII'AMIN Lle'aowrrzPatented June 15, 1954 [TED STATES OFFICE Benjamin Liebowitz, Lewisboro,N. Y.

Application March 18, 1952, Serial No. 277,165

23 Claims. 1

In my copending U. S. patent applications Serial No. 190,092, filedOctober 14, 1950, now Patent No. 2,601,035, dated June 17, 1952, forWearing Apparel and Methods of Producing the Same; Serial No. 199,317,filed December 5, 1950, now Patent No. 2,601,036, dated June 17, 1952,for Articles of Wearing Apparel; Serial No. 217,341, filed March 24,1951, now Patent No. 2,601,037, dated June 17, 1953, for Collars andMethod for Preventing Curling of Collars; and Serial No. 247,910, filedSeptember 24, 1951, now Patent No. 2,601,038, dated June 17, 1952, forAnticurl Devices for Collars, of which the present application is acontinuation-in-part, I have disclosed devices for causing acountercurling tendency in a garment part to oppose the curling forcesimposed on such garment part by the wearing thereof. For instance, thepoints of collars and the tops of girdles often tend to curl away fromthe body of the wearer; in the aforesaid applications it is shown how tooppose this curling tendency by anticurling forces produced by abielastic structure comprising a flexible compression-resistantsubstantially nonstretchable element and a flexible permanentlystretched elastic element attached in permanent tension-creating stateto said compression-resistant element. Moreover, in my patentapplication Serial No. 247,910, I have pointed out that a verysignificant improvement is obtained in the functioning of the anticurldevices by having variable tension in the elastic element so as tocreate anticurling forces which are stronger in some regions than inothers.

The object of this invention is to provide methods and apparatus for themanufacture of such antiourl strips, viz. apparatus and methods forfeeding two strips, one a flexible compressionresistant substantiallynon-stretchable tape and the other a flexible elastic substantiallynon-compression-resistant strip or tape, e. g. a rubber tape, atrequired relative rates into a uniting machine, e. g. a sewing machine,so that the resulting composite bielastic tape structure will have thedesired stretch in the rubber; and where that stretch is variable, thedesired distribution of stretch along its length.

The method and apparatus for achieving this object will be understood byreference to the accompanying drawings, in which:

Fig. 1 is a diagrammatic isometric View of an arrangement designed tofeed an elastic rubber tape at a predetermined rate relative to thefeeding of a substantially non-stretchable tape so as to produce auniform stretch in the elastic rubber tape relative to thisnon-stretchable tape;

Fig. 1A is a graph showing the relationship between percentageelongation of the rubber tape and distance along the composite tapeproduced by the apparatus of Fig. 1;

Fig. 2 is a diagrammatic isometric view of an apparatus for feeding anelastic tape at a variable predetermined rate relative to the feeding ofa substantially non-stretchable tape so as to produce a stretch in theelastic tape having a predetermined approximately sinusoidal variationalong the length of the composite bielastic tape;

Fig. 2A is a graph showing the relationship between the stretch orpercentage elongation of the rubber and the distance along the compositebielastic tape as produced by the arrangement of Fig. 2;

Fig. 3 is a diagrammatic isometric View of an apparatus similar to theapparatus shown in Fig. 2, but equipped with a cam instead of aneccentric roll;

Fig. 4 is a side elevation of an apparatus operating on the sameprinciples as the apparatus shown in Fig. 2;

Fig. 5 is a side elevation of an apparatus op-. erating on the sameprinciples as the apparatus shown in Fig. 1;

Fig. 6 is a rear side elevation showing an arrangement for electricallyoperating a cutoff device of the type shown in Fig. 4;

Fig. '7 is a side elevation of a modification of the apparatus shown inFig. 4 and operating primarily, but not altogether, on the principles ofthe apparatus shown in Fig. 2; and

Fig. 8 is an end elevation-as seen from the right of Fig. 7-of theapparatus shown in Fig. 7.

Referring to Fig. 1, the needle of a sewing machine is diagrammaticallyindicated at H in association with-the presser foot 12 of the machine.As a feeding mechanism on the sewing machine I prefer to employ a pairof rolls 13-! 3A behind the presser foot instead of the usual feeddogarrangement. These rolls are intermittently driven in proper relation tothe needle motion so as to produce the desired feed.

The work being fed consists of two tapes, one shown at it, being acompression-resistant relatively non-stretchable cotton or other tape,e. g. a woven tape treated with resin or a woven tape employingrelatively large monofilaments in the warp. The other tape shown at itis an elastic tape preferably made of rubber, e. g. of the kind used inso-called elastic garment tape. The ccmpressiomresistant non-stretchabletape 14 is fed over a feed roll or drum HS which rotates at such a ratethat its peripheral speed is equal to the rate of feed of the feed rollsi3i3A. In practice I have found that the best method in this type ofapparatus for producing equality of rate of feed due to the feed rolls13-!3A and the rate of feed due to the rotation of the feed drum i6 isto drive the feed drum it by means of the non-stretchable tape It whichis pulled at any desired rate by the feed rolls l3-l 3A.

The feed roll is is mounted on a shaft l which in turn is mounted inappropriate bearings not indicated in the diagrammatic Figures 1, 2 and3. Mounted on the same shaft [7 and concentric with the drum It is asmaller drum l8 over which the elastic, stretchable tape i must pass.The working surfaces of both drums, that is, the surfaces which are incontact with the respective tapes, are roughened to produce a highcoefficient of friction, e. g. by pasting strips of emery cloth over theperipheral faces of the drums. The di ameter of the drum I8 is chosen soas to produce a rate of feed of the elastic tape is lower than the rateof feed of the non-stretchable tape is by a predetermined amount so asto produce a uniform predetermined tension or elongation in the elastictape. The formula for determining the elongation E in the rubber taperelative to the other tape is 16 lS D16 E-ZTI' 2WD; DIS 1 Where D16 isthe diameter of the large feed roll it and D18 is the diameter of thesmall stretching roll l8.

Certain idler rolls for pressing the tapes it and I5 against theirrespective feed rolls are omitted from Fig. 1 in the interest of claritybut are shown in the corresponding Fig. 5.

The functioning of the device of Figure 1 will now be obvious: Thesewing machine parts i i, it? and 53A are driven at a specified rate offeed so as to feed the non-stretchable tape ht at that specified rate.The tape it thereby drives the synchronizer roll it so that itsperipheral speed ,is equal to the rate of feed produced by the stitchingapparatus. This in turn determines the speed and hence rate of feed ofthe smaller stretching roll I 8, whose smaller peripheral speed causes aslower rate of feed of the rubber tape to produce the desired stretch inthe rubber as indicated in the formula above. The two tapes aresuperimposed by appropriate guides and sewn together by the stitchingmechanism of the machine diagrammatically indicated by the needle H andthe presser foot [2.

For purposes of comparison with modifications described below, I haveshown in Figure 1A a graph showing the elongation of the rubber tape asa function of the distance along the finished composite bielastic tape.In this particular case the elongation does not vary as one goes alongthe tape, i. e. it is uniform.

Now, as mentioned above, a very important improvement in anticurlingproperties results from making the tension or stretch in the rubbervariable along the finished bielastic strip. Figure 2 shows amodification of the apparatus of Figure 1 showing how the desiredperiodic variation in tension is obtained. It will be seen that theessential difference between the apparatus of Figure 1 and that ofFigure 2 is that the rubber feeding roll 18 of Figure l is concentricwith the shaft l1 and roll !5, whereas in Figure 2 the rubber feedingroll now indicated by 58E, is eccentrically mounted on the shaft [1. Theeffect of this eccentric mounting is to cause a variation in the rate offeed of the rubber tape [5 relative to the rate of feed of the tape isbecause the point of tangency T at which the rubber tape It leaves theroll iSE is closer to the axis of shaft [7 at one point of its cycle butmuch farther from the axis of shaft I? at another point of the cycle andit is the distance of this point of tangency from the axis of the shaft[1 that determines the rate of feed at any given instant. The relativevariation in tension is determined not only by the throw of theeccentric but also by the distance from the point of tangency T to theneedle. An approximate formula for the elongation E as a function of theangular position A of the eccentric I813 is the following:

when D16 and D18 are the diameters of rolls It and IBE, respectively, eis the eccentricity (distance between roll centers) and R. is thedistance from the point of tangency T to the needle M. This formulagives the instantaneous elongation as the stitching proceeds. Theaverage elongation of the rubber is approximately given by the sameformula as for Figure 1.

Figure 2A is a graph showing diagrammatically how the tension orelongation of the rubber varies approximately sinusoidally along thecomposite bielastic tape produced by the apparatus of Figure 2. It willbe seen that there are points A, C, etc. where the tension is minimum,and other points B, etc. where the tension is maximum. The tape issubsequently cut at or near each point of maximum and minimum tension sothat the resulting composite strip will have a maximum tension at ornear one end and a minimum tension at or near the other end. It will beunderstood furthermore that each revolution of the roll It produces twofinished tapes. Since prescribed lengths of strip will in general berequired, the diameter of the drum I6 is preferably chosen so that thelength of its periphery is just equal to the lengths of the two finishedbielastic tape elements. Again, it will be understood that certain idlerrolls are employed in the apparatus shown in Figure 2 which are notshown in this figure but are shown in the corresponding Figure 4.

Finally, it will be understood that the eccentric 98E of Figure 2 ismerely one form of a cam. Other cam forms may be employed, e. g. asdiagrammatically shown at [8C of Figure 3. This latter type of cam makesfour bielastic strips for each revolution of the feed roll it.

Figure 4 shows a side elevation of the essential parts of a completeapparatus similar to the one diagrammatically shown in Figure 2. InFigure 4, l is the table top and 2 is the base of a conventional sewingmachine. ll indicates the needle and I2 the presser foot as before; i3and lBa, are a pair of feed rolls which are driven by the sewing machineaccording to well known methods. The non-stretchable tape [4 is pulledoff a roll 3| and passes around an idler roll 32 so that it is pressedbetween the idler roll 32 and the working surface 33 (shown dotted) ofthe synchronizer roll 16, the working surface 33 being the bottom of agroove which is covered with emery cloth. The idler 32 is carried by alever 34 which is pivoted on a pin 35 which is carried in the uprightmember 36, the said upright member 36 forming essentially the base ofthe entire feeding mechanism. After passing approximately 180 around theworking surface 33, the non-stretchable tape it then passes underanother idler roll 3'! which is carried on a lever 38 pivoted at 39 on apin which is also carried by the upright member 36. The two idler rolls32 and 31 are pressed against the working surface 33 by means of atension spring connecting the two levers 34 and 38. Only one end of thisspring is indicated at 48 on lever 34. After leaving the nip between theidler roll 31 and the working surface 33 the non-stretchable tape l4passes to a guide 4! which is just ahead of the presser foot 12. Thetape is guided under the presser foot l2 by a groove in the bottom ofthe same indicated by the dotted line; the presser foot guides andcontrols the tapes but exerts no vertical pressure on them. Thestretching mechanism thus is driven at a continuous rate determinedentirely by the rate of feed of the feed rolls [3 and 13a.

Eccentrically carried on the face of the drum I5 is a grooved roll ordisc 42. The bottom of the groove of 42 indicated by the dotted line 43is the working surface of the roll 42 and serves as a feed roll fordetermining the rate of feed of the rubber tape 15. This tape is fedwithout appreciable tension from a roll or spool 44 and passes around anidler roll 45 which presses against the bottom of the groove thatconstitutes the working surface 43 in the feed roll 42. The feed roll isfor the non-stretchable tape i4 is mounted on a shaft 45, which iscarried in bearings mounted on the upright member 36. The feed roll 42is fastened to the side of the feed roll is so as to have the desiredeccentricity with respect to the shaft 46 as diagrammatically indicated.As a result of this eccentricity the idler roll 45 which coacts with theworking surface 43 of the feed roll 42 must be capable of movement toand away from the center of the shaft 45. To allow for this movement theidler roll 45 is rotatably mounted on the end of a lever 4'! which ispivotally mounted on pin 48 carried by an ex tension arm 49 mounted onthe upright member 35. A tension spring 56 whose tension is adjustableby means of the screw and nut device 5i pulls the lever 41 upward so asto press the idler roll 45 against the coacting working surface 43.

The rubber tape i5 is thereby caused to move between the nip of theworking surface 43 and the idler roll 45 so that its speed is determinedby the peripheral speed of the working surface 43. Due to the eccentriclocation of this working surface the said rate of feed is periodicallyvariable as described in connection with Figure 2. From the nip betweenthe working surface 43 and the idler roll 45 the rubber tape i5 passesunder the guide 4! there joining in superposed relation with thenon-stretchable tape it. The two tapes then pass under the needle sothat they are sewn together one on top of the other.

The composite bielastic tape takes the curly form indicated at X at theexit end of the apparatus. Here an electrical solenoidal cutoff deviceis shown at 52' which comprises a plunger 53 operated by the solenoid incasing 522 and carrying at its upper end a cutoff knife 54. This cutoffknife co-acts with an anvil 55 at an appropriate instant determined bythe momentary switching on of the operating current for the solenoid 52at the proper moment in the cycle of operations, as will be describedbelow. For certain purposes it is preferable not to cut the tape apartby a cutoff mechanism shown at 54, 55 but merely to mark the tape with agood clear mark so that it can be cut off subsequently at the time thatthe tape is sewn into a collar, for example. A convenient Way of markingthe tape for this purpose is by heated means similar to cutoff knife 54,but with reduced energy in the solenoid. Current for operating thesolenoid 52 is carried to the solenoid by the leads 56A and 56B. Themethod of momentarily switching on the current will be described below.

For certain purposes it is desirable to use a heated cutoff knife 54even when the tapes are cut apart and not merely marked. Thus, when thenon-stretchable tape M has nylon monofils in its warp to make itcompression-resistant, it is desir-able to heat-seal the ends of thetape to fix the nylon monofils at their ends. This heatsealing isreadily accomplished by heating the cutoff blade 54.

Furthermore, I have found it sometimes convenient and advisable to usenylon sewing thread in place of the usual cotton sewing thread. Also inthis event, it is advantageous to use a heated cutoff or marking blade54 in order to seal the ends of the nylon sewing threads as well as toseal the ends of the nylon monofils.

Figure 5 is a side elevation of an apparatus which functions so as toprovide a uniform elongation or tension in the rubber in the same manneras the apparatus shown in Figure 1.

It will be understood that in this machine the same sewing machineelements and other parts are used as in the apparatus shown in Figure tand hence only the modified stretching and thus tensioning feedmechanism of the machine is shown, in Figure 5. The non-stretchable tapeI4 comes up from below and passes around the working surface SI of theroll 66, the said working surface 6! being the bottom of a groove cut inthe roll it and surfaced with emery cloth. The roll i6 rotates on theshaft H which is mounted in a block $2. The two vertical bars 63A and93B are pressed at their bottom ends into the block 62 and at their topends into the bar 64. Another block as is bored so that it may slide onthese bars. This block 65 carries a shaft 66 on which an idler roll 61rotates freely. This idler roll 6'! co-acts with the working surface 6|in the roll iii. A spring 68 whose compressive force is adjustable bymeans of the screw 69 urges the block 65 downward so as to cause theidler roll er to press against the working surface it! of the roll 55.The relatively nonstretchable tape 24 is caused to pass between the nipof the idler roll 5? and the working surface 6: so that the rate of feedof the tape I4, which is determined by the rate of feed of the sewingmachine, determines the rate at which the synchronizing feed roll l5rotates. Concentric with the feed roll iii in accordance with Figure 1is the stretching feed roll I8 which is rigidly connected to thesynchronizing feed roll it so that the two rotate at the same speed. Therubber tape l5 passes around an idler roll l0 and then around theworking surface H, shown in dotted lines, which is the bottom of agroove cut in the roll 13. The idler roll "it! is mounted so as torotate freely on a pin l2 which is carried at the bottom end of the arm73 which in turn is pivoted at 'E4 on the top member 54 of the assembly. A spring '15 whose compressive force is adjustable by means of thenut 15 urges the arm 73 to the left, thereby causing the idler roll itto press against the working surface ll of the drum :e. The rubbertapetherefore after passing part-way around the idler 10, passes between thenip of the roll I and the working surface H and then continues incontact with the working surface of H until it emerges tangentiallytherefrom as shown. Thus, the two tapes emerge side by side but at adifferential rate of feed determined by the first formula given above.

Referring now to Figures 7 and 8, in these figures a mechanism isillustrated which operates primarily on the same principle as theapparatus shown in Figures 2 and 4 but in addition incorporates stillother means for Varying the tension of the elastic tape as will beexplained. In the embodiment shown in Figures 7 and 8 there is also thepractical advantage that the two tapes go through the feeding mechanismwith their central lines co-planar. In these figures, Hi indicates thenon-stretchable tape as before, which passes around a grooved pulley it.As before, the bottom of the groove is covered with emery cloth so as tocreate high friction between the non-stretchable tape [4 and the pulleyIS, thereby ensuring positive drive of the pulley it by the tape M.Again 42 indicates an eccentric which rotates on shaft it. Unlike Figure4, the axis of rotation of pulley it does not coincide with the axisshaft of rotation of the eccentric 432, but the two axes are separatedand spaced parallel to each other, as shown in Figure 7. The drive ofthe eccentric :32 is now obtained by means of the gear lll mounted onthe shaft 48, the idler gear H2 and the gear H3 mounted on shaft #25. InFigure 7 the diameter of the eccentric 42 is chosen so that it gives therequired average stretch of the rubber tape when the gear ratio betweenH i and H3 is 1 to 1. It will be readily understood, however, that anyconvenient diameter can be chosen for the eccentric t2 and then the gearratio can be chosen so as to give the required average stretch to therubber tape.

The shafts 36, 46', as well as the shaft for the idler gear H2 are allmouthed on a plate H which acts as a base for the entire mechanism. Asin Figure 7, an idler roll is shown at H6 which presses the tape Magainst the grooved pulley it so as to insure positive drive of thepulley i6 by the tape I l. To obtain this pressure, a torsion spring H1urges the lever i 58 toward the pulley it, the pulley H6 being rotatablymounted on the end of the lever i 58.

As before, the elastic tape i5 is pressed against the bottom of a groovein eccentric 32, e, g. by means of a small pair of closely spaced rollsH9 swiveled at the end of lever I26 which in turn is pivotally mountedon the base H5 at lZi. A torsion spring i22 presses on the lever 520 soas to press the roller pair i l9 and hence the rubber tape against thebottom of the groove in eccentric which again is covered with emerycloth so that the instantaneous rate of feed of the rubber tape isdetermined entirely by the rate of feed given to it by the eccentric 42,as a function of the angular position of eccentric t2. Rotatably mountedat l23 at the end of lever lid is a roller in over which the rubber tapepasses on its way from the nips between eccentric 42 and the roller pairH9 to the guide roll I25 and thence to the sewing machine. It will beunderstood that in general the instantaneous rate of feed of the rubberis determined as in the apparatus shown in Figure 4 by the position ofthe eccentric in its cycle, the rate of feed being a minimum in theposition shown in Figure '7, that is, where the hip is closest to theaxis 46. A half-revolution later the nip will rise to the point whereits distance from the shaft 46' is a maximum; at this point the rate offeed is a maximum; also at this point the roller 524 will have movedinto the position indicated by the dotted lines at lz ia. It will alsobe clear that the path of the rubber tape l5 from the nip in itsuppermost position over the roller in the osition 424a and thence underthe roller I25 is shorter than the corresponding path of the tape fromthe nip in its lowest position as indicated by the solid lines in Figure'7, that is, from the nip over roller I24 and thence under roller I25.This variation in the length of the path of the rubber tape constitutesan additional means for varying the tension. With the nip shown in theposition of Figure '7, the rate of feed is a minimum and the path lengthover 124 and 125 is a maximum, hence both effects contribute towardsmaking the tension of the rubber a maximum in the configuration shown bythe solid lines of Figure '7. On the other hand, a half revolutionlater, the rate of feed is a maximum and the path length of the rubbertape over the rolls is a minimum and both effects contribute towardsmaking the tension in the rubber a minimum. It is a fact that thislatter means can be used alone to obtain variable stretch and tension inthe rubber. That is to say, the rate of feed of the rubber tape l5 canbe made constant relative to the rate of feed of the non-stretchabletape M, in accordance with the scheme shown in Figure 1 and Figure 5,and an eccentric or other means can be used to move a pulley such as I24cyclically so as to vary the length of the rubber periodically in itspath from its feed roll to the guide of the sewing machine.

The actuating mechanism for the cutoff means described above inconnection with Figure 4, is shown in Figure 6, including mainly thoseparts which are necessary to explain the operation of this cutoffmechanism.

The shaft I! extends through the rear of the vertical base member 35 andcarries a disc iill so that the said disc rotates at the same speed asthe roll 15. This disc Hll carries two pins 862A and B so that everyhalf revolution one of them comes in contact with a roller I 33 of amicroswitch I84, thereby closing at every half cycle the microswitch It?for a short time interval. The phase in the cycle where this circuitclosing occurs is determined by the angular position of either the disc1 ill or the microswitch EM. Hence, one or both of these angularpositions is made adjustable so that the cutoff can be produced at theright moment in the cycle. Current from a power supply is carriedthrough leads IGEA and B of the microswitch to the solenoid leads 56Aand B of Figure 4 so that the closure of the microswitch by either pinEMA or B will energize the solenoid 52 of Figure 4 and cause it tooperate the cutoff mechanism. In order to avoid dependence of theoperation of the cutofi mechanism on the length of time during which themicroswitch is closed by the mechanisms as indicated, which time ofclosure may be too long and also may be variable, I prefer other methodsof determining the time interval during which the solenoid 52 of Figure4 is energized. In practice I have found it convenient to use a circuitin which a condenser is charged through a suitable resistance during theperiod preceding each operation of the solenoid and in which closure ofthe microswitch lfi l operates a relay which discharges the saidcondenser into a relay which operates the solenoid 52. Details of such 9a circuit are known in the electrical engineering art and need not begiven here.

The cutoff device shown mainly in Figures provides a simple solution foran otherwise difficult roblem connected with the cutting off of thecontinuous bielastic tape as produced by the machine into short lengthsrequired for use in collars, when the tension in the rubber is variable.Suppose, for example, that attempt was made to out such continuousbielastic tape into short strips of equal length after the continuousstrip has been removed from the machine. Even if an accurate startingpoint could be found, a few thousandths of an inch error in each lengthof strip would produce an error amounting to an inch or more in thelocation of the cutoff with respect to the region of minimum (ormaximum) tension after a few hundred or a thousand of such strips hadbeen cut from the continuous bielastic tape because of unavoidablecumulative errors. The apparatus illustrated in Figures 4 and 6 isdesigned to eliminate such cumulative errors and relies on a method ofcutting the bielastic tape as it emerges from the machine at or close tosuch position in the bielastic tape where the tension in the rubber is aminimum or a maximum, the position of the cutofi being determined by thephase in the cycle of operation of the machine itself when theinstantaneous tension produced by the machine is an extremum (i. e. aminimum or maximum).

To avoid unnecessarily cumbersome language, I have referred to the feedproduced by the rolls I3-l3A as continuous, also implying that it isuniform in contrast to the variable rate of feeding of the rubber tapein the apparatus of Figure 2. As a matter of fact, as everyone skilledin the art knows, on most sewing machines the feed produced by the rollsI3--I3A would actually be far from continuous; for instance, if themachine makes 3,600 stitches per minute, the feed rolls l3ltA will startand stop 60 times per second, so that there is no feed during theinterval when the needle l is in the work. Due to elasticity of tape M,which drives the pulley I6 (despite the fact that the said tape has beendescribed as substantially non-stretchable), and also due to theelasticity of other parts, and due finally to the inertia of all theparts which are moved when the tape it is fed by the rolls l3-!3A, theintermittent feeding of the work by the rolls l3l 3A will be, to someextent, smoothed out so that the motion of the roll it and all partsassociated with it will not follow rigorously the intermittent motion ofthe rolls l3l 3A. Instead the motion of the roll I6 and its associatedparts will be a rippling one which, for practical purposes associatedwith this invention may be regarded as continuous, ince the ripples willoccur at a rate of about 60 ripples per second, more or less.

I claim:

1. Method of manufacturing bielastic tape elements comprising incombination the steps of feeding along a predetermined path,superimposed upon and facing each other a compressionresistantsubstantiallynon-stretchable tape and an elastic tape in considerablystretched tensioncreating condition; cyclically varying the degree ofstretch of said elastic tape so that during each of said cycles thestretch ranges between a maximum and a minimum; fastening saidcompression-resistant tape and said elastic tape to each other alongtheir entire length While the stretch of the latter is cyclically variedand said tapes are fed along said predetermined path in superimposedcondition, thus obtaining a continuous bielastic tape structure composedof said elastic tape fastened to one face of said compressionresistanttape and having in the direction of its length consecutive zones in eachof which the stretch of said elastic tape ranges between a maximum inthe region of one end thereof and a minimum in the region of the otherend thereof; and severing said continuous bielastic tape structurebetween each two consecutive zones thereof in synchronism with anddepending upon said cyclical variations of the degree of stretch of saidelastic tape and at substantially the same phase of each of saidcyclical variations so as to obtain a plurality of bielastic tapeelements each composed of an elastic tape portion fastened to acompression-resistant tape portion so as to induce in the same acurvature which ranges between a maximum in the region of one endthereof and a minimum in the region of the other end thereof and is inthe direction of that face of said com-- prssion-resistant tape portionto which said elastic tape portion is fastened.

2. Method of manufacturing bielastic tape elements comprising incombination the steps of feeding along a predetermined path,superimposed upon and facing each other a compressionresistantsubstantially non-stretchable tape and an elastic tape in considerablystretched tensioncreating condition; cyclically varying the degree ofstretch of said elastic tape so that during each of said cycles thestretch ranges between a maximum and a minimum; fastening saidcompression-resistant tape and said elastic tape to each other alongtheir entire length while the stretch of the latter is cyclically variedand said tapes are fed along said predetermined path in superimposedeondition, thus obtaining a continuous bielastic tape structure composedof said elastic tape fastened to one face of said compressionresistanttape and having in direction of its length consecutive zones in each ofwhich the stretch of said elastic tape ranges between a maximum and aminimum; and severing said continuous bielastic tape structure betweeneach two consecutive zones thereof in synchronism with and dependingupon said cyclic variations of the degree of stretch of said elastictape and at substantially the same phase of each of said cyclicvariations so as to obtain a plurality of bielastic tape elements, eachcomposed of an elastic tape portion fastened to a compressionresistanttape portion so as to induce in the same a curvature which rangesbetween a maximum and a minimum and is in the direction of that face ofsaid compression-resistant tape portion to which said elastic tapeportion is fastened.

3. Method of manufacturing bielastic tape elements comprising incombination the steps of feeding along a predetermined path,superimposed upon and facing each other a compressionresistantsubstantially non-stretchable fabric tape and an elastic rubber tape inconsiderably stretched tension-creating condition; cyclically varyingthe degree of stretch of said elastic rubber tape so that during each ofsaid cycles the stretch ranges between a maximum and a minimum;fastening said compression-resistant tape and said elastic rubber tapeto car. along their entire length while the stretch the latter iscyclically varied and said are fed along said predetermined path insuperimposed condition, thus obtaining a continuous cielastic tapestructure composed of said elastic rubber tape fastened to one face ofsaid compression-resistant fabric tape and having in direction of itslength consecutive zones in each of which the stretch of said elasticrubber tape ranges between a maximum in the region of one end there ofand a minimum in the region of the other end thereof; and severing saidcontinuous bielastic tape structure between each two consecutive zonesthereof in synchronism with and depending upon said cyclic variations ofthe degree of stretch of said elastic rubber tape and at substantiallythe same phase of each of said cyclic variations so as to obtain aplurality of bielastic tape elements each composed of an elastic rubbertape portion fastened to a compression-resistant fabric tape portion soas to induce in the same a curvature which ranges between a maximum inthe region of one end thereof and a minimum in the region of the otherend thereof and is in the direction of that face of saidcompression-resistant fabric tape portion to which said elastic rubbertape portion is fastened.

4. Method of manufacturing connected bielastic tape elements comprisingin combination the steps of feeding along a predetermined path,superiznposed upon and facing each other a compression-resistantsubstantially non-stretchable fabric tape and an elastic rubber tape inconsiderably stretched tension-creating condition; cy-

clically varying the degree of stretch of eiastic rubber tape so thatduring each of said cycles the stretch ranges between a maximum and aminimum; fastening said compression-resistant fabric tape and saidelastic rubber tape to each other along their entire length while thestretch of the latter is cyclically varied and said tapes are fed alongsaid predetermined path in cups"- imposed condition, thus obtaining acontinuous bielastic tape structure composed of said elastic rubber tapefastened to one face of said compression-resistant fabric tape andhaving in direction of its length consecutive zones in each of which thestretch of said elastic rubber tape ranges between a maximum in theregion of one end thereof and a minimum in the region of the other endthereof; and marking said continuous bielastic tape structure betweeneach two consecutive zones thereof so as to obtain a plurality ofconnected bielastic tape elements each composed of an elastic rubbertape portion fastened to a compressionresistant fabric tape portion soas to induce in the same a curvature which ranges between a maximum inthe region of one end thereof and a minimum in the region of the otherend thereof and is in the direction of that face of saidcompression-resistant fabric tape portion to which said elastic rubbertape portion is fastened.

5. Method of manufacturing connected b;- elastic tape elementscomprising in combination the steps of feeding along a predeterminedpath, superimposed upon and facing each other a compression-resistantsubstantially non-stretchable tape and an elastic tape in considerablystretched tension-creating condition; cyclically varying the degree ofstretch of said elastic tape so that during each of said cycles thestretch ranges between a maximum and a minimum; fastening saidcompression-resistant tape and said elastic tape to each other alongtheir entire length while the stretch of the latter is cyclically variedand said tapes are fed along said predetermined path in superimposedcondition, thus obtaining a continuous bielastic tape structure composedof said elastic tape fastened to one face of said compression-resistanttape and having in direction of its length consecutive zones in each ofwhich the stretch of said elastic tape ranges between a maximum in theregion of one end thereof and a minimum in the region of the other endthereof; and marking said continuous bielastic tape structure betweeneach two consecutive zones thereof in synchronism with and dependingupon said cyclical variations of the degree of stretch of said elastictape and at substantially the same phase of each of said cyclicalvariations so as to obtain a plurality of connected bielastic tapeelements each composed of an elastic tape portion fastened to acompression-resistant tape portion so as to induce in the same acurvature which ranges between a maximum in the region of one endthereof and a minimum in the region of the other end thereof and is inthe direction of that face of said compression-resistant tape portion towhich said elastic tape portion is fastened.

6. Method of manufacturing bielastic tape elements comprising incombination the steps of feeding along a predetermined path,superimposed upon and facing each other a compressionresistantsubstantially non-stretchable tape and an elastic tape in considerablystretched tensioncreating condition; cyclically varying the degree ofstretch of said elastic tape so that during each of said cycles thestretch ranges between a maximum and a minimum; fastening saidcompression-resistant tape and said elastic tape to each other alongtheir entire length while the stretch of the latter is cyclically variedand said tapes are fed along said predetermined path in superimposedcondition, thus obtaining a continuous bielastic tape structure composedof said elastic tape fastened to one face of said compression-resistanttape and having in direction of its length consecutive zones in each ofwhich the stretch of said elastic tape ranges between a maximum and aminimum; and severing said continuous bielastic tape structure betweeneach two consecutive zones thereof so as to obtain a plurality ofbielastic tape elements, each composed of an elastic tape portionfastened to a compression-resistant tape portion so as to induce in thesame a curvature which ranges between a maximum and a minimum and is inthe direction of that face of said compression-resistant tape portion towhich said elastic tape portion is fastened.

'7. Method of manufacturing bielastic tape elements comprising incombination the steps of feeding along a predetermined path,superimposed upon and facing each other a compression-resistantsubstantially non-stretchable tape and an elastic tape in considerablystretched tension-creating condition; cyclically varying the degree ofstretch of said elastic tape so that during each of said cycles thestretch ranges bel which the stretch of said elastic tape ranges betweena maximum in the region of one end thereof and a minimum in the regionof the other end thereof; and severing said continuous bielastic tapestructure between each two con- 'secutive zones thereof so as to obtaina plurality of bielastic tape elements each composed of an elastic tapeportion fastened to a compressionresistant tape portion so as to inducein the same a curvature which ranges between a maximum in the region ofone end thereof and a minimum in the region of the other end thereof andis in the direction of that face of said compression-resistant tapeportion to which said elastic tape portion is fastened.

8. Apparatus for manufacturing 'a bielastic tape structure comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; stretching means arranged in the path of the pulledelastic tape for stretching the same, during pulling by said feedingmeans, said stretching means including a means for cyclically varyingthe tension of said stretching means during each of the cycles between amaximum and a minimum so as to for in said stretched elastic tapeconsecutive zones in each of which the stretch of the tape rangesbetween a maximum and a minimum; and driving means for operating saidstretching means during operation of said feeding means.

9. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; stretching means arranged in the path of the pulledelastic tape for stretching the same, during pulling by said feedingmeans, said stretching means including a means for cyclically varyingthe tension of said stretching means during each of the periods betweena maximum and a minimum so as to form in said stretched elastic tapeconsecutive zones in each of which the stretch of the tape rangesbetween a maximum and a minimum; anddriving means operated insynchronism with said feeding means and operating said'stretching meansso that the same stretches said elastic tape in synchronism with saidfeeding means pulling both tapes into the uniting means.

10. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for feeding into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; stretching means arranged in the path of the fedelastic tape for stretching the same, during feeding by said feedingmeans, said stretching means including a means for cyclically varyingthe tension of said stretching means during each of the cycles between amaximum and a minimum so as to form in said stretched elastic tapeconsecutive zones in each of which the stretch of the tape rangesbetween a maximum and minimum; and driving means for operating saidstretching means during operation of said feeding means.

11. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for feeding into saiduniting means along predetermined paths a compression-resistant tape andan elastictape; stretching means arranged in the path -'of the fed"elastic tape forstretching the same, during feeding by said feedingmeans, said stretching means including a means for cyclically varyingthe tension of said stretching means during each of the cycles between amaximum and a minimum so as to form in said stretched elastic tapeconsecutive zones in each of which the stretch of the tape rangesbetween a maximum and a minimum; and driving means operated insynchronism with said feeding means and operating said stretching meansso that the same stretches said elastic tape in synchronism with saidfeeding means feeding both tapes into the uniting means.

12. Apparatus for manufacturing bielastic tape elements comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; stretching means arranged in the path of the pulledelastic tape for stretching the same, during pulling by said feedingmeans, said stretching means including a means for cyclically varyingthe tension of said stretching means during each of the cycles between amaximum and a minimum so as to form in said strethed elastic tapeconsecutive zones corresponding to said cycles and in each of which thestretch of the tape ranges between a maximum and a minimum; drivingmeans for operating said stretching means during operation of saidfeeding means; cutting means arranged after said uniting means in thepath of the joined tapes; operating means for operating said cuttingmeans;'and actuating means interconnectin said operating means with saidstretching means for periodic actuation of said operating means at thesame phase of each stretching cycle of said stretching means so as toseversaid joined tapes between each two consecutive zones of saidelastic tape.

13. Apparatus for manufacturing connected bielastic tape elementscomprising in combination uniting means for fastening to each otheralong their lengths two superimposed tapes; feeding means for pullinginto said uniting means along predetermined paths acompression-resistant tape and an elastic tape; stretching meansarranged in the path of the pulled elastic tape for stretching the same,during pulling by said feeding means, said stretching means including-ameans for cyclically varying the tension of said stretching means duringeach of the cycles between a maximum and a minimum so as to form in saidstretched elastic tape consecutive zones corresponding to said cyclesand in-each of which the stretch of the tape ranges between a mum and aminimum; drivingmeans for-operav ing said stretching means duringoperation of said feeding means; marking means arranged after saiduniting'means-in the path of the joined tapes; operating means foroperating saidmarking means; and actuating means interconnecting saidoperating means with said stretching means for periodic actuation ofsaidoperating means at the same phase of each stretching cycle of saidstretching means so as to mark said joined tapes between each twoconsecutive zones of said elastic tape.

14. Apparatus for manufacturing connected bielastic tape elementscomprising in combination uniting means for fastening to each otheralong their lengths two superimposed tapes; feed ing means for pullinginto said uniting means along predetermined paths acompression=resistant tape and an elastic tape; a rotatable synchronizermember arranged in the path of the pulled compression-resistant tapenon-slidably engaging the same and rotated by said tape during pullingof the tape by said feeding means; stretching means arranged in the pathof the pulled elastic tape for stretching the same, duling pulling bysaid feeding means, said stretching means including a means forcyclically varying the tension of said stretching means during each ofthe cycles between a maximum and a minimum so as to form in saidstretched elastic tape consecutive zones corresponding to said cyclesand in each of which the stretch of the tape ranges between a maximumand a minimum; driving means operated by said rotatable synchronizermember and operating said stretching means so that the same stretchessaid elastic tape in synchronism with the feeding means pulling bothtapes into the uniting means; marking means arranged after said unitingmeans in the path of the joined tapes; operating means for operatingsaid marking means; and actuating means interconnecting said operatingmeans with said stretching means for periodic actuation of saidoperating means at the same phase of each stretching cycle of saidstretching means so as to mark said joined tapes between each twoconsecutive zones of said elastic tape.

15. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to a compression-resistant tapepassing through said uniting means an elastic tape superimposed uponsaid compressionresistant tape along the length thereof; feeding meansfor pulling said elastic tape at uniform speed into said uniting means;stretching means arranged in the path ofthe pulled elastic tape forstretching the same, during pulling by said feeding means, saidstretching means including a means for cyclically varying tensionproduced by said stretching means during each of the cycles between amaximum and a minimum so as to form in said stretched elastic tapeconsecutive zones in each of which the stretch of the tape rangesbetween a maximum and a minimum; and driving means for operating saidstretching means during operation of said feeding means.

16. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; a rotatable synchronizer member arranged in the path ofthe pulled com- 'pression-resistant tape; means for maintaining thecompression-resistant tape in non-slidable engagement with saidsynchronizer member so that the latter is rotated by saidcompressionreslstant tape during pulling of the latter tape by saidfeeding means; stretching means arranged in the path of the pulledelastic tape for stretching the same during pulling by said fee ingmeans; and driving means operated by said rotatable synchronizer memberand operating said stretching means so that the same stretches saidelastic tape in synchronism with the feeding means pulling both tapesinto the uniting means.

17. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along preill determined paths a compression-resistant tapeand an elastic tape; a rotatable synchronizer roller arranged in thepath of the pulled compression-resistant tape; means for maintaining thecompression-resistant tape in non-slidable engagement with saidsynchronizer roller so that the latter is rotated by saidcompression-resistant tape during pulling of the same by said feedingmeans; a rotatable stretching roller arranged in the path of saidelastic tape ncn-slidably en-. gaging the same; and driving meansoperated by said synchronizer roller and rotating said stretching rollerso that the peripheral speed of said stretching roller is less than thepulling speed of said feeding means, resulting in stretching of theelastic tape pulled by said feeding means in synchronism with saidfeeding means pulling both tapes into the uniting means.

18. Apparatus for manufacturing bielastic tape elements comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; a rotatable synchronizer member arranged in the path ofthe pulled compression-resistant tape; means for maintaining thecompression-resistant tape in non-slidable engagement with saidsynchronizer member so that the latt r is rotated by said tape duringpulling of the latter by said feeding means; stretching means arrangedin the path of the pulled elastic tape for stretching the same duringpulling by said feeding means with the degree of tension exerted by saidstretching means on said elastic tape periodically varying during eachof the periods between a maximum and a minimum so as to form in saidstretched elastic tape consecutive zones in each of which the stretch ofthe tape varies between a maximum and a minimum; driving means operatedby said rotatable synchronizer member and operating said stretchingmeans so that the same stretches said elastic tape in synchronism withthe feeding means pulling both tapes into the uniting means; cuttingmeans arranged after said uniting means in the path of the joined tapes;operating means for operating said cutting means; and actuating meansinterconnecting said operating means with said stretching means forperiodic actuation of said operating means at the same phase of eachstretching period of said stretching means so as to sever said joinedtapes between each two consecutive zones of said elastic tape.

19. Apparatus for manufacturing a biela-stic tape structure comprisingin combination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; a rotatable synchronizer roller arranged in the path ofthe pulled compression-resistant tape; means for maintaining thecompression-resistant tape in non-slidable engagement with saidsynchronizer roller so that the latter is rotated by saidcompression-resistant tape during pulling of the same by said feedingmeans; a stretching roller having a smaller diameter than said rotatablesynchronizer roller and arranged in the path of said elastic tapenon-slidably engaging the same, said stretching roller being arrangedrotatably about an eccentric axis so as to exert during its rotation onsaid elastic tape a tension periodically varying between a maximum and aminimum and to form in the elastic tape stretched by periodicallyvarying tension consecutive zones in each of which the stretch of thetape varies between a maximum and a minimum; and driving means operatingby said rotatable synchronizer member and rotating said stretchingroller about its eccentric axis so that the same stretches said elastictape in synchronism with the feeding means pulling both tapes into theuniting means.

20. Apparatus for manufacturing bielastic tape elements comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; a rotatable synchronizer roller arranged in the path ofthe pulled compression-resistant tape; means for maintaining thecompression-resistant tape in non-slidable engagement with saidsynchronizer roller so that L the latter is rotated by saidcompression-resistant tape during pulling of the same by said feedingmeans; a stretching roller arranged in the path of said elastic tapenon-slidably engaging the same, said stretching roller being arrangedrotatably about an eccentric axis so as to exert during its rotation onsaid elastic tape a tension periodically varying between a maximum and aminimum and to form in the elastic tape stretched by said periodicallyvarying tension consecutive zones in each of which the stretch of thetape varies between a maximum and a minimum; driving means operated bysaid rotatable synchronizer member and rotating said stretching rollerabout its eccentric axis in such a manner that the average peripheralspeed of said stretching roller is less than the pulling speed of saidfeeding means so that said stretch-- ing roller stretches said elastictape in synchronism with the feeding means pulling both tapes into theuniting means; cutting means arranged after said uniting means in thepath of the joined tapes; operating means for operating said cuttingmeans; and actuating means interconnecting said operating means withsaid stretching roller for periodic actuation of said operating means atthe same phase of each stretching period of said stretching roller so asto sever said joined tapes between each two consecutive zones of saidelastic tape.

21. Apparatus for manufacturing bielastic tape elements comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; a rotatable synchronizer member arranged in the path ofthe pulled compression-resistant tape; means for maintaining thecompression-resistant tape in non-slidable engagement with saidsynchronizer member so that the latter is rotated by said tape duringpulling of the latter by said feeding means; a rotatable stretchingmember arranged in the path of the pulled elastic tape for stretchingthe same during pulling by said feeding means with the degree of tensionexerted by said rotatable stretching member on said elastic tapeperiodically varying during each of the periods between a maximum and aminimum so as to form in said stretched elastic tape consecutive zonesin each of which the stretch of the tape varies between a maximum and aminimum; driving means operated by said rotatable synchronizer memberand operating said rotatable stretching member so that the samestretches said elastic tape in synchronism with the feeding meanspulling both tapes into the uniting means; cutting means arranged aftersaid uniting means in the path of the joined tapes; operating means foroperating said cutting means; and actuating means interconnecting saidopera-ting means with said rotatable stretching member for periodicactuation of said operating means at the same phase of each stretchingperiod of said rotatable stretching member so as to sever said joinedtapes between each two consecutive zones of said elastic tape.

22. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to each other along theirlengths two superimposed tapes; feeding means for pulling into saiduniting means along predetermined paths a compression-resistant tape andan elastic tape; a rotatable synchronizer roller arranged in the path ofthe pulled compression-resistant tape; means for maintaining thecompression-resistant tape in non-slidable engagement with saidsynchronizer roller so that the latter is rotated by saidcompression-resistant tape during pulling of the same by said feedingmeans; a rotatable cam-shaped stretching member arranged in the path ofsaid elastic tape non-slidably engaging the same so as to exert duringits rotation on said elastic tape a tension periodically varying betweena maximum and a minimum and to form in the elastic tape stretched bysaid periodically varying tension consecutive zones in each of which thestretch of the tape varies between a maximum and a minimum; and drivingmeans operated by said rotatable synchronizer roller and rotating saidrotatable cam-shaped stretching member so that the same stretches saidelastic tape in synchronism with the feeding means pulling both tapesinto the uniting means.

23. Apparatus for manufacturing a bielastic tape structure comprising incombination uniting means for fastening to a compression-resistant tapepassing through said uniting means an elastic tape superimposed uponsaid compression-resistant tape along the length thereof; feeding meansfor pulling said elastic tape at uniform speed into said uniting means;stretching means arranged in the path of the pulled elastic tape forstretching the same, during pulling by said feeding means, saidstretching means including a means for cyclically varying the tension ofsaid stretching means during each of the cycles between a maximum and a,minimum so as to form in said stretched elastic tape consecutive zonesin each of which the stretch of the tape ranges between a maximum and aminimum; and driving means operated in synchronism with said feedingmeans and operating said stretching means so that the same stretchessaid elastic tape in synchronism with said feeding means pulling bothtapes into the uniting means.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,022,851 Galligan et al. Dec. 3, 1935 2,022,852 Galligan eta1. Dec. 3, 1935

